Moistureproof article



Patented Nov. 9, 1937 UNITED STATES PATENT OFFICE MOISTUREPROOF ARTICLEware No Drawing. Application December 21, 1934,

Serial No. 758,658

19 Claims. 91-70) This invention relates to the art of moistureproofing.More particularly, it relates to a composition of matter suitable forthe production of moistureproof materials and also to the moistureproofmaterials per se. I

We believe that moistureproofing is due to 1) the use of an agent whichis inherently moistureproof, and (2) the laying down of this agent in acontinuous unbroken film, either alone or in combination with othermaterials or vehicles hereinafter called film-forming substances.

We have found, as a result of a large number of experiments, thatsubstances are inherently moistureproof when they are of such a naturethat they are not only insoluble in water but also dissolve none or atleast only an infinitesimal amount of water. Apparently, water vapordiffuses through continuous unbroken films of such substances by aprocess of dissolving in the film so and evaporating from the otherside. The solubility of water in the moistureproofing agent largelydetermines the rate of transfusion of water vapor through the film, andtherefore its inherent moistureproofness. Obviously, if the film isnon-continuous and broken, other factors enter into the determination ofthe degree of moistureproofness. y

We have found that organic halogen compounds of the type hereafter morefully described can be used in the preparation of moistureproofingcompositions which will yield moistureproof films, i. e. coatings orself-sustaining films which are preferably also transparent, glossy,non-tacky, flexible, possess good surface slip, etc.

For the purposes of this specification and claims, we definemoistureproof materials as those which, in the form of continuousunbroken sheets or films, permit the passage of not more than 570 gramsof water vapor per 100 square meters per hour, over a period of 24hours, at approximately 35 C.:t0.2 C., the relative humidity of theatmosphere at one side of the film being maintained at least at 98% andthe relative humidity of the atmosphere at the other side beingmaintained at such a value as to give a humidity differential of atleast 95%.

Moistureproofing coating compositions are defined as those which, whenlaid down in the form of a thin, continuous, unbroken film applieduniformly as a coating with a total coating thickness not exceeding0.0005" to both sides of a sheet of regenerated cellulose of thicknessapproximately 0.0009", will producea coated product which ismoistureproof For the purpose of experimental tests, especially forthose materials adaptable as coating compositions, moistureproofmaterials include those substances, compounds or compositions which,when laid down in the form of a continuous unbroken film applieduniformly as acoat- 5 ing with a total coating thickness not exceeding0.0005 to both sides of a sheet of regenerated cellulose of thicknessapproximately 0.0009", will produce a coated sheet which will permit thepassage therethrough of not more than 5'70 grams 10 of water vapor per100 square meters per hour over a period of approximately 24 hours, at atemperature of 35 C.:0.2 C., with a water vapor pressure differential of40-44 mm. (preferably 41.8i0.7 mm.) of mercury. For convenience, I

the number of grams of water vapor passed under these conditions may bereferred to as the permeability value. An uncoated sheet of regeneratedcellulose having a thickness of approximately 0.0009" will show apermeability value of the order of 5700.

From the foregoing, it is apparent that under the conditions set forth,a moistureproofed regenerated cellulose sheet is capable of resistingthe passage of moisture or water vapor therethrough at least 10 times aseffectively as the uncoated regenerated cellulose sheet.

We have specifically defined herein moistureproofness in terms of apermeability test performed at substantially 35 C. It is to beunderstood, however, that by the adoption of this condition nodisclaimer is made of moistureproob. ness of any of the materials orcompositions when tested at temperatures lower than C. Likewise, nodisclaimer is made of moistureproof- 35 ing efiects exhibited by thematerials herein described at temperatures above 35 C. There will bea'temperature for each moistureproofing agent above which neither it norcompositions containing it show substantial resistance to the 40 passageof moisture. However, this behavior does not disqualify the materialsherein described as moistureproofing agents.

The critical temperature above which these agents no longer exhibitmoistureproof properties is dependent primarily upon the melting pointof the material and upon the nature and composition of the film-formingsubstance with which it is used. Agents of higher melting points willshow moistureproof properties up to higher temperatures than will agentsof low melting points, other conditions being equal. Generally speaking,the agents of higher melting points will be preferred for this reason,though for. certain other mixed aliphatic-aromatic or purposes it maybe. definitely advisable to use agents of iower melting points.

It is, therefore, an object of this invention to provide a compositionof matter suitable for casting or coating purposes comprising afilm-forming substance and an organic halogen compound, more fullydescribed hereafter, which will deposit a moistureprooi film, i. c. aself-sustaining film or coating which is preferably also transparent,flexible, non-tacky, glossy and possesses good surface slip.

Another object of this invention is to provide moistureproof films, i.e. self-sustaining films or coatings containing organic halogencompounds which impart moistu'reproofness thereto, said films beingpreferably also transparent, flexible, non-tacky, glossy and possessinggood surface slip.

Other objects will become apparent from the following description andappended claims.

The instant invention, in one phase thereof, contemplates a fiowablecomposition of matter which will deposit a moistureproof film, i. e.selfsustaining film or coating which, in the preferred embodiment, istransparent (glass-clear), flexible, glossy, non-tacky, and possessesgood surface slip. The composition consists of an agent which affordsthe basis for moistureproofness, and a film-fanning substance. In thepreferred embodiment, the composition also includes a solvent or solventmixture, a plasticizer and/or a blending agent.

As the agents which afford the basis .for the moistureproofness, theinstant invention contemplates solidorganic halogen compounds which areinherently moistureproof and have a melting point of at least 37 C. Themolecule of the moistureproof acids is largely hydrocarbon carbon, butmay contain the usual modifying groups, such as hydroxyl, carbonyl,ester, etc., providing it has a sufilciently high hydrocarbon carboncontent to oifset the affinity for water for these substituent groups.In so far as this specification is concerned, a hydrocarbon carbon atomis one which has at least three of its valences attached to carbon orhydrogen.

When an organic halide containing no modifying group in the molecule isused as the moistureprooflng agent, we have found that the molecule mustcontain at least 18 hydrocarbon carbon atoms in the hydrocarbon portionthereof for the halogen atom in order to achieve a moistureproofingeffect. When more than 18 hydrocarbon carbon atoms are present, bettermoistureproofing eflects are secured.

The organic halides contemplated by the instant invention may bealiphatic or aromatic or cyclic, or they may be a derivative of anorganic halogen compound containing additional active groups. Any groupor atom other than hydrocarbon is considered an active group. We havefound that, when the number of active groups is increased, for example,when two similar active groups are present, the limiting ratio may be55%-66% of the limiting ratio for one such group, while for threesimilar active groups the limiting ratio is 45%55% and approaches alimiting value of 30% as the number of similar active groups is furtherincreased. When different active groups are introduced, the limitingratio of hydrocarbon carbon atoms will vary, dcpendingon the nature andnumber of such groups. Thus, for example, if two different active groupsare present, the limiting ratio of hydrocarbon carbon atoms to activegroups will be 55%-66% of the mean of the limiting ratio for each of theindividual active groups.

Chlorotriacontane, ceryl bromide, di-hcptadecyl methyl chloride, etc.are specific illustrative examples of organic halides which aremoistureproof and can be utilized in the preparation of moistureprooffilms.

As previously mentioned, the composition also contains a film-formingsubstance. As illustrative examples of film-forming substances may bementioned cellulose derivatives, for example, cellulose nitrate,cellulose acetate, ethyl cellulose, benzyl cellulose, mixed esters orether esters: resins, either natural or synthetic, such as rosin,hydrogenated rosin and its derivatives, including glycerol, glycol ordiethylene glycol esters of hydrogenated rosin; rosin esters ofglycerol, glycol or diethylene glycol; gum dammar; polybasicacid-po1yhydric alcohol resins, either-modified or unmodified; vinylresins of the polymerized vinyl acetate, polymerized chlor-vinyl acetateand polymerized vinyl acetal resin types; metastyrene resin; phenoliccondensation products; rubber, gutta percha, balata, caoutchouc;synthetic rubbers, including polymers of isoprene, butadiene and theirhomologues; chemicalderivatives of rubber, such as halogenated rubber,rubber treated with sulphuric acid, rubber treated with tintetrachloride; rubber treated with chlorostannic acid; varnishes; etc.One or a plurality of film-forming ingredients may be used. The precisefilm-forming ingredient or mixture thereof depends upon the purpose forwhich the compositions are to be used.

When the composition contains a softener, any suitable softener for thefilm-forming ingredient may be used. For example, diamyl phthalate,trlcresyl phosphate, dicyclohexyl phthalate, butyl benzoyl benzoate etc.may be used, when the filmforming ingredient is a cellulose derivative.

In some compositions wherein a cellulose derivative is used, the filmwhich is produced may be hazy. If desired, this may be overcome byincorporating in such a composition a blending agent. Such compositionsare also generally more moistureproof than those without the blendingagent or gum. The blending agent tends to improve the compatibility ofthe moistureproofing agents with the other ingredients in the film andconsequently the impermeability of the film. As several illustrativeexamples of blending agents may be mentioned gums or resins, such asdammar, gum elemi, ester gum,

hydrogenated rosin; hydrogenated ester gum or the like, halogenateddiphenyl, a natural occurring balsam or a synthetic balsam-likesubstance, such as diethylene glycol hydrorosinate, or a substance suchas lanurn, hydrogenated castor oil, di-dodecyl phthalate, retene,diricinoleic ester of glycerol or the like.

The ingredients which constitute the final film may be dissolved in anappropriate solvent or solvent mixture to form a solution which may beused as herein described. Alternatively, the ingredients constitutingthe final film may be used in the form of a melt. When the compositionis to be used in the form of a melt, it is desirable to include thereina blending agent to inhibit crystallization. Hydrogenated rubber,hydrogenated ester gum, rosin, dammar, diethylene glycol hydrorosinateand the like, are several illustrative examples of crystallizationinhibitors. Whenever the composition is in the form of a lacquer andused for coating purposes,

the solvents thereof are chosen so that they will not produce anydeleterious eiIects on the base being coated.

The proper formulation of the lacquer so that it will yield coatingswhich are transparent and highlymoistureproof is determined by tests.One of the most important things to be determined is the proper amountof blending agent to be used. This can be determined, for example, asfollows: A series of compositions is prepared containing the sameamounts of lacquer base, softener, moistureproofing agent and solvent.Different quantities of blending agent ar'then added to each of theselacquers and the general properties, such as 'transparency and thepermeability values of sheets of regenerated cellulose, for example,coated with each of these compositions, are plotted against the ratio ofblending agent to moistureproofing agent used.

when a lacquer of the type described in Example IV is modified accordingto this systematic procedure, it will be found that the lowestpermeability value occurs very near the point where the coatings becomecompletely transparent. In the case of chlorotriacontane in thisparticular composition, this point is equivalent to approximately 2.00to 4 grams of dammar to 1. gram of chlorotriacontane. It is obvious thatthis optimum blending agent-moistureproofing agent ratio will vary fordifferent moistureproofing agents and for different blending agents withthe same moistureproofing agent. In general, this ratio depends upon thehydrocarbon carbon content and the solubility of the moistureproofingagent in the lacquer solids. Thus, the ratio is high formoistureproofing agents having high hydrocarbon carbon content and lowfor moistureproofing agents which are quite soluble or compatible withthe other constituents of the coating. Undoubtedly, other factors, suchas melting point, solvent composition of the lacquer, type of lacquerbase used, choice of plasticizer, etc. also affect this optimum ratio,but the two considerations mentioned above seem to be the more importantones.

A series of experiments, based on the composition of Example IV, will,of course, have 'a pyroxylin lacquer .base and apyroxylin-moistureproofing agent ratio of 5.26:1. Obviously, this ratiocan also be varied and the relations between permeability value and theblending agent-moistureproofing agent ratio determined for sheets ofregenerated cellulose coated with a series of lacquers having adifferent lacquer base-moistureproofing agent ratio to which variousamounts of dammar or other blending agent have been added. Theserelations will have the same general character but it will be foundgenerally that, as the lacquer base-moistureproofing agent ratio isincreased (decreasing the quantity of moistureproofing agent), thepenneability values will be higher for a given blendingagent-moistureproofing agent ratio and will eventually pass out of themoistureproof limit. On the other hand, decreasing this ratio(increasing the moistureproofing agent) does not decrease thepermeability values indefinitely and, after a certain point is reached,may even decrease the moistureproofness. Experiments have shown that theoptimum lacquer base-moistureproofing agent ratio usually falls withinthe limits 1:10 to 200:1 and the blending agentmoistureproofing agentratio lies between the limits of 0:1 to 10:1. The most satisfactorycellulose derivative base-moistureproofing lacor vehicles.

quers generally fall within these limits for nearly all moistureproofingagents, the optimum pyroxylin-moistureproofing agent ratios being of theorder of 2:1 to 30:1. However, for certain purposes, for example,compositions for casting moistureproof foil, the ratios may difiergreatly from those given above and we do not intend that we should beconfined to these limits which are suggested merely as an aid to theproper formulation of moistureproofing lacquers.

The above or any other method for determining the most satisfactoryformula in which to use any moistureproofing agent to achieve minimumpermeability and maximum clarity of coating may be used. The abovediscussion is merely given as one systematic method, wherebycompositions may be formulated with the moistureproofing agents heredisclosed. Different moistureproofing agents will yield different dataon such a series of experiments as this, and moistureproofing agents ofdifferent chemical constitution will be formulated differently intovarious dopes There is thus no single composition such as has beendescribed above which is capable of universal application. The specificexamples hereafter given are thus illustrative, and the above-describedmethod of systematically varying the compositions of solids in which amoistureproofing agent is used is exemplary of a general method, wherebyoptimum results may be achieved with an agent. The method is, of course,capable of extension to include variations of any of the solid lacqueringredients, or even to include solvents and the solvent composition.Thus, when one skilled in the artis taught by these disclosures, he willbe able to formulate a variety of compositions containing any of themoistureproofing agents or to determine those compositions with whichour moistureproofing agents are most advantageously used. Amoistureproofing agent is thus not a material which will always anduniversally produce moistureproof coatings utterly regardless of thecomposition in which it is used. It usually requires to be formulated incertain favorable compositions to bring out its inherentmoistureproofing properties. On the other hand, a substance which is notinherently moistureproof cannot by andextended amount of work informulation be made to yield moistureproof films or coatings. Thus, whenwe speak of the inherent property of a compound to moistureproof, we areconcerned with a specific inherent property which permits it to be usedwith some film-forming vehicle to produce moistureproof coatings.

The composition can be used for the production of films, either bycasting it in the well-known manner to produce self-sustaining films, orby coating iton to the selected base. When the composition is to be usedas a coating, any suitable base material, paper, highly calenderedpaper, glassine, leather, fabrics, etc. may be used. The compositionsmay even be applied to metals to prevent them from rust by virtue oftheir moistureproofing property. They may also be used to coatindividual fibers of cotton, wool or artificial silk in such a manner asto make them moisture proof. In the preferred embodiment of theinvention, when a transparent wrapping tissue is desired, the base mayconsist of thin, dense, nonfibrous, substantially non-porous andpreferably transparent sheeting formed of a cellulosic, albuminous orother material. As illustrative examples of cellulosic sheeting may bementioned cellulosic sheeting coagulated or precipitated irom an aqueousdispersion or solution ofa celluloslc material, for example, sheeting ofregenerated cellulose, glycol cellulose, cellulose glycollic acid, lowlyetherifled or esterified cellu1ose, such as lowly methylated cellulose;and sheeting of cellulose derivatives, such as cellulose acetate,cellulose nitrate, ethyl cellulose, benzyl cellulose. Gelatin andcasein, hardened or not as desired, are mentioned as illustrativeexamples of albuminous materials. Sheeting of rubber or rubberderivatives may also be used as the base.

When a selected base as, for example, regenerated cellulose sheeting isto be moistureproofed by the compositions hereinbefore described, thecomposition is applied to the regenerated cellulose sheeting in anysuitable manner, such as immersion, spraying, brushing, etc. The lacquermay be, if necessary, maintained at the time of application at anelevated temperature in order to prevent separation of themoistureprooflng ingredients. The excess composition is removed by anysuitable means and substantially all the volatile solvents are removedfrom the composition at an elevated temperature, for example C.- C., inorder to prevent separation or crystallization of the moistureproofingagent during evaporation of the solvent. It is also preferable to useair low in moisture content during the drying operation in order toobtain evaporation of the solvent without film blush. After being dried,the product, if the base is of the type which loses moisture at elevatedtemperatures, may be subjected to a humidifying treatment or other meansfor a sufllcient time to impart or restore flexibility and to deodorize.In some cases, the lacquercoated materials may be air-dried at roomtemperature, in which case the humidifying treatment is not needed.

Hereafter, there are set forth several illustrative specific examples inorder to more clearly explain the invention:

Emmple I (A) A composition consisting of the following ingredients inapproximately the proportions set forth is prepared in any convenientand appropriate manner:

Parts by weight Pyroxylin 5.26. Gum dammar 3.25 Dibutyl phthalate 2.32Ceryl bromide 1.00 Ethyl acetate 46.25 Toluene 36.00 Alcohol 6.28

Acetone 0.68

. A transparent sheet of regenerated cellulose is submerged in thislacquer which, for convenience, is maintained at a temperature of 40 C.in order to prevent separation of the moistureproofing agent. The excesslacquer is removed by suitable means and the coated sheet is dried,preferably promptly, at an elevated temperature and preferably also inair at 90 C.-110 C. The coated sheet is glass-clear in transparency,flexible, non-tacky, glossy, possesses good surface slip and is onlyapproximately 0.00005" to 0.00015" thicker than the uncoated sheet andit is practically impossible to distinguish the coated sheet from theuncoated sheet in appearance. However, the coated sheet ismoistureproof, having a permeability value of less than 570, for exampleof the order of 285 or even less.

The coated sheet is much more resistant to the passage of water vaporthan a similar sheet coated with the same lacquer except for theomission of ceryl bromide or a sheet coated with a high grade waterproofspar varnish. A sheet coated with the lacquer without the addition ofceryl bromide will have a permeability value of 4,000 to 5,000, whilethe sheet coated with a waterproof spar varnish will have a permeabilityvalue of from 2,000 to 4,000.

(B) vCeryl bromide in Example I(A) above is substituted by an equalamount of dl-heptadecyl methyl chloride. The process of Example I(A) isutilized to coat transparent regenerated cellulose sheeting. The productpossesses the same I characteristics as the product of Example I(A).

A composition consisting of the following ingredients in approximatelythe proportions set forth is prepared by any well-known procedure:

Parts by weight Ethyl cellulose 6.0 Rosin 3.6 Tricresyl phosphate 1. 0Chlorotriacontane 1. 0 Toluene 60.0 Alcohol 19.0

This composition is suitable for coating sheets of cellulose acetate andsuch coated sheets will have a permeability value of the order of orless. This product is also transparent, flexible, glossy, non-tacky andpossesses good surface slip.

As previously explained, in many cases it may be desirable to omit thegum or resin entirely, though when used it may materially improve thetransparency of the final product.

Example III A composition consisting of the following ingredients inapproximately the proportions set forth is prepared in any well-knownmanner:

Parts by weight Ethyl cellulose 7. 0 Dibutyl phthalate 2.0 Ceryl bromide1.0 Toluene 62.0 Alcohol 21.0

Transparent sheets of cellulose acetate are coated with this compositionas described in Example I(A) and dried at room temperature for 10minutes. The coated sheets have a permeability value of the order of 285or less.

The above composition becomes useful for airdried coatings, if 10 partsby weight of ethyl lactate are added thereto to avoid blushing.Compositions of this type may be used for protecting steel and othercorrodible metals against rust or the like. These coatings may beairdried at room temperature for 10 minutes and are at least 20 times asimpermeable as similar coatings containing no moistureproofing agents.

Example IV V Parts by weight Pyroxylin 5. 26 Dlbutyl phth 2. 32

Chlorotriacontane 1.00 Ethyl acetate 46. 25 Toluene 36, ()0 Alcohol 6.28 Ac n 0. 68

Transparent sheets of regenerated cellulose are coated and treated inthe manner described in Example HA). The product has a permeabilityvalue of not more than 570.

The compositions described in Examples III and IV yield coatings whichmay be slightly hazy. If transparency is essential, a blending agent ofthe type above mentioned may be incorporated in this composition. Thus,for example, the lacquer described in Example IV may be so modifled thatit always will yield transparent coatings by the addition of a blendingagent such as dammar. The quantity of dammar or other blending agent tobe added must be determined as previously described.

The following is an example of a composition wherein a polybasicacid-polyhydric alcohol resin constitutes the film-forming ingredient.This composition consisting of the following ingredients inapproximately the proportions given is prepared in any suitable manner:

Parts by weight *Perilla oil-polybasic acid-polyhydric alcohol resinvarnish 50.0 Di-heptadecyl methyl chloride 1.0 Toluene 50.0

*The perilla oil polybasic acid-polyhydric alcohol resin varnish isprepared from the following ingredients:

Parts byweight Ethyl acetate 800.0

The procedure for preparing the perilla oil polybasic acidpolyhydricalcohol resin varnish is as follows:

Heat 72.6 parts of C. P. glycerin to 350 F. in closed kettle-condenserand stirrer. At 350 F. add NaOH, followed by perilla oil. Stir rapidlyand heat to 437 F. Hold until clear (15-30 minutes). Add phthalicanhydride and heat to 392 F. Add residue of glycerin to batch. Heat to392 F. and hold (5 hours). Acid number 45- 55. Cool to 175 F. Cut withethyl acetate. Add drier and centrifuge. (Solids 50%.)

Regeneratedcellulose sheeting coated with this composition, as explainedunder Example I(A), and dried at room temperature, or at C.- C.,produces a product having a permeability value of the order of or less.A composition of this type may be used without blending agents, but insome cases it is advantageous to use a small amount of a blending agent.Usually compositions of this nature are sufliciently flexible withoutthe addition of a plasticizer. Lacquers of this type may be used whenparticularly good adhesion .is desired.

As previously mentioned, another method of obtaining articles which areof themselves moistureproof is the casting of films containing theorganic halides as moistureproofing agents. The

compositions given in Examples I to IV may be used for this purpose. It,is usually desirable, however, to employ a higher solids base solutionfor. casting sheets than is ordinarily used for forming thin coatings.Furthermore, in view of the greater thickness of cast foils as comparedto coatings, a smaller proportion of the moistureproofing agent is usedin order to obtain transparency and a high degree of moistureproofness,and this in turn will require the use of a smaller quantity of blendingagent and/or the use of blending agents other thanhard gums inappreciable quantities. Those skilled in the art will be able toformulate by tests satisfactory compositions for the preparation of castsheets.

The cast sheets and protective coatings prepared in accordance with theinstant invention have the ability to resist the transmission ordiffusion of water vapor to an extent at least 4 times that displayed bysheets of equal thickness and produced from similar or prior artcompositions formulated without the addition of moistureproofing agents.The value 4'merely sets forth the minimum improvement and does not limitthe higher moistureproofness thatcan be obtained. The moistureproofingagents herein described are capable of being formulated into fihnsshowing improvement over prior art films produced from compositionsformulated without the addition of moistureproofing agents not only 4but 10, 20, 40 and in some cases even 100 fold. This is truly aremarkable accomplishment.

The compounds described in this application as moistureproofing agentshave .nany advantages. Moistureproofing compositions containing themoistureproofing agents are easily duplicated. As previously stated,these compositions in certain formulations thereof yield coatings whichair-dry at ordinary temperatures. For certain purposes where it is notfeasible to force-dry the coatings, this becomes especially important.As for the moistureproofing agents themselves, they are generallycolorless, odorless, tasteless, nonvolatile, and essentially non-toxic,at'least in the quantities in which they are used, and they can bereproduced synthetically with a high degree of uniformity andconsistency.

In the definition hereinbefore set forth, it is to be understood thatthe permeability value of 5'70 represents only the maximum value. Inmany cases permeabilities of 235, 140, 5'7, 30 or indeed less may beobtained.

When bases of the preferred type are utilized. the ultimate product isadmirably suited for use as a transparent moistureproof wrapping tissue.

Since it is obvious that various changes and modifications may be madein the above description without departing from the nature or spiritthereof, this invention is not restricted thereto except as set forth inthe appended claims.

We claim:

1. An article of manufacture having a continuous unbroken moistureproofsurface comprising a film-forming substance and an organic halogencompound having a melting point of at least 37 C. as themoistureproofing agent, said organic halogen compound containingno othermodifying groups in the molecule and being selected from the class whichconsists of (1) mono-halides containing at least 18 hydrocarbon carbonatoms for the halogen group, (2) di-halides containing at least 10hydrocarbon carbon atoms for each halogen group, (3) tri-halidescontaining at least 8 hydrocarbon carbon atoms for each halogen group,(4) tetra or higher halides containing at least 5 hydrocarbon carbonatoms foreach halogen group,-said organic halogen compound being presentinan amount to impart moistureproofness to the article.

2'. An article of manufacture comprising a continuous unbrokenmoistureproof film comprising a film-forming substance and an organichalogen compound having a melting point of at least 37 C. as themoistureproofing agent, said organic halogen compound containing nomodifying groups in the molecule and being selected from the class whichconsists of (1) mono-halides containing at least 18 hydrocarbon carbonatoms for the halogen group, (2) di-halldes containing at least 10hydrocarbon carbon atoms for each halogen group, (3) tri-halidescontaining at least 8 hydrocarbon carbon atoms for each halogen group,(4) tetra or higher halides containing at least 5 hydrocarbon carbonatoms for each halogen group, said organic haliogen compound beingpresent in an amount to impart moistureproofness to the article.

3. An article of manufacture comprising a continuous unbrokenmoistureproof film comprising a film-forming substance, an organichalogen compound having a melting point of at least 37 C. as themoistureproofing agent and a blending agent, the ratio of the quantityof film-forming substance to the quantity of organic halogen compoundbeing within the limits of 1: 10 to 200: 1 and the ratio of the quantityof blending agent to the quantity of organic halogzn compound beingwithin the limits of :1 to 10:1, said organic halogen compoundcontaining no modifying groups in the molecule and being selected fromthe class which consists of (l) mono-halides containing at least 18hydrocarbon carbon atoms for the halogen group, (2) di-halidescontaining at least 10 hydrocarbon carbon atoms for each halogen group,(3) tri-halides containing at least 8 hydrocarbon carbon atoms for eachhalogen group, (4) tetra or higher halides containing at leasthydrocarbon carbon atoms for each halogen group, said organic halogencompound being present in an amount to impart moistureproofness to thearticle.

4. An article of manufacture comprising a continuous unbrokenmoistureproof film comprising pyroxylin, an organic halogen compoundhaving a melting point of at least 37 C. as the moistureproofing agentand a blending agent, the ratio of the quantity of pyroxylin to thequantity of organic halogen compound being within the limits of 2:1 to30:1, said organic halogen compound containing no modifying groups inthe molecule and being selected from the class which consists of (1)mono-halides containing at least 18 hydrocarbon carbon atoms for thehalogen group, (2) di-halides containing at least 10 hydrocarbon carbonatoms for each halogen group, (3) trihalides containing at least 8hydrocarbon carbon atoms for each halogen group, (4 tetra or higherhalides containing at least 5 hydrocarbon carbon atoms for each halogengroup, said organic halogen compound being present in an amount toimpart moistureproofness to the article.

5. An article of manufacture having a continuous unbroken moistureproofsurface comprising a film-forming substance and an organic halogencompound having a melting point of at least 37 C. as themoistureproofing agent, said organic halogen compound containing noother modifying groups in the molecule and containing at least 18hydrocarbon carbon atoms for the halogen group, said organic halogencompound being present in an amount to impart moistureproofnes's to thearticle.

-6. An article of manufacture comprising a continuous unbrokenmoistureproof, film comprising a film-forming substance and an organichalogen compound having a melting point of at least 37 C. as themoistureproofing agent, said organic halogen compound containing noother modifying groups in the molecule and containing at least 18hydrocarbon carbon atoms for the halogen group, said organic halogencompound being present in an amount to impart moistureproofness to thearticle.

7. An article of manufacture comprising a continuous unbrokenmoistureproof film comprising a film-forming substance, an organichalogen compound having a melting point of at least 37 C. as themoistureproofing agent and a blending agent, the ratio of the quantityof film-forming substance to the quantity of organic halogen compoundbeing within the limits of 1:10 to 200:1

and the ratio of the quantity of blending agent to organic halogencompound being within the limits of 0:1 to 10:1, said organic halogencompound containing no other modifying groups in the molecule andcontaining at least 18 hydrocarbon carbon atoms for the halogen group,said organic halogen compound being present in an amount to impartmoistureproofness to the article.

8. An article of manufacture having a continuous unbroken moistureproofsurface comprising a film-forming substance and chlorotriacontane as themoistureproofing agent, the latter being present in an amount to impartmoistureproofness to said article.

9. An article of manufacture having a continuous unbroken moistureproofsurface comprising a film-forming substance and ceryl bromide as themoistureproofing agent, the latter being present in an amount to impartmoistureproofness to said article.

10. An article of manufacture having a continuous unbroken moistureproofsurface comprising a film-forming substance and di-heptadecyl methylchloride as the moistureproofing agent, the latter being present in anamount to impart moistureproofness to said article.

11. An article of manufacture comprising a base having a continuousunbroken moistureproof coating comprising a film-forming substance andan organic halogen compound having a melting point of at least 37 C. asthe moistureproofing agent, said organic halogen compound containing nomodifying groups in the molecule and being selected from the class whichconsists of (1) mono-halides containing at least 18 hydrocarbon carbonatoms for the halogen group, (2) di-halides containing at least 10hydrocarbon carbon' atoms for the halogen group, (3) trihalidescontaining at least 8 hydrocarbon carbon atoms for each halogen group,(4) tetra or higher halides containing at least 5 hydrocarbon carbonatoms for each halogen group, said organic halogen compound beingpresent in an amount to impart moistureproofness to the article.

12. An article of manufacture comprising a transparent non-fibrous basesheet or film having a continuous unbroken transparent moistureproofcoating comprising a film-forming substance and an organic halogencompound having a melting point of at least 37 C. as themoistureproofing agent, said organic halogen compound containing nomodifying groups in the molecule and being selected from the class whichconsists of (1) mono-halides containing at least 18 hydrocarbon carbonatoms for the halogen group, (2) di-halides containing at least 10hydrocarbon carbon atoms for the halogen group, (3) trihalidescontaining at least 8 hydrocarbon carbon atoms for each halogen group,(4) tetra or higher halides containing at least 5 hydrocarbon carbonatoms for each halogen group, said organic halogen compound beingpresent in an amount to impart moistureproofness to the article.

13. An article of manufacture comprising a transparent regeneratedcellulose base sheet or film having a continuous unbroken transparentmoistureproof coating comprising a film-forming substance and an organichalogen compound having a melting point of at least 37 C. as themoistureproofing agent, said organic halogen compound containing nomodifying groups in the molecule and being selected from the class whichconsists of (1) mono-halides containing at least 18 hydrocarbon carbonatoms for the halogen group, (2) di-halides containing at least 10hydrocarbon carbon atoms for the halogen group, (3) tri-halidescontaining at least 8 hydrocarbon carbon atoms for each halogen group,(4) tetra or higher halides containing at least 5 hydrocarbon carbonatoms for each halogen group, said organic halogen compound beingpresent in an amount to impart moistureproofness to the article.

14. An article of manufacture comprising a base having a continuousunbroken moistureproof coating comprising a film-forming substance andan organic halogen compound having a melting point of at least 37 C. asthe moistureproofing agent, said organic halogen compound containing noother modifying groups in the molecule and containing at least 18hydrocarbon carbon 37 C. as the moistureproofing agent, said organichalogen compound containing no other modifying groups in the moleculeand containing at least 18 hydrocarbon carbon atoms for the halogengroup, said organic halogen compound being present in an amount toimpart moistureproofness to the article.

16. An article of manufacture comprising a transparent regeneratedcellulose base sheet or film having a continuous unbroken transparentmoistureproof coating comprising a film-forming substance and an organichalogen compound having a melting point of at least 37 C. as themoistureprooflng agent, said organic halogen compound containing noother modifying groups in the molecule and containing at least 18hydrocarbon carbon atoms for the halogen group, said organic halogencompound being present in an amount to impart moistureproofness to thearticle.

17. An article of manufacture comprising a transparent non-fibrous basesheet or film having a continuous unbroken transparent coatingcomprising a film-forming substance and chlorotriacontane as themoistureproofing agent, the latter being present in an amount to impartmoistureprooiness to said article.

18. An article of manufacture comprising a transparent non-fibrous basesheet or film having a continuous unbroken transparent coatingcomprising a film-forming substance and ceryl bromide as themoistureproofing agent, the latter being present in an amount to impartmoistureproofness to said article.

19. An article of manufacture comprising a transparent non-fibrous basesheet or film having a continuous unbroken transparent coatingcomprising a film-forming substance and diheptadecyl methyl chloride asthe moistureproofing agent, the latter being present in an amount toimpart moistureproofness to said article.

WILLIAM HALE CHARCH. MERLIN MARTIN BRUBAKER. FREDERICK M. NIEIGS.

